1. Field of the Invention
This invention relates to a position-monitoring device for persons in tunnel systems, equipped with an evaluation device.
2. Discussion of Related Art
German Patent Reference DE 10 2005 055 102 A1 discloses a method for detecting, locating, and managing objects with an inventory or resources management system and an associated apparatus. In this known method, mobile object nodes and stationary anchor nodes, each with a processing unit, a transceiver unit, a memory unit, a power supply, and an individual identification, and one or more mobile or stationary access nodes that also have an input/output unit, form a self-generating network for wireless communication. The anchor nodes in this case are situated at known positions and each object to be monitored is assigned to an object node. A data exchange between the individual nodes takes place either directly or by a multi-hop process and in order to monitor the objects, the access node or nodes query data from the object nodes and/or receive data transmitted from the object nodes, either automatically or by individual request. The method permits a spontaneous overview of current numbers and current locations of the respective objects as well as an optional overview of other information about the object and its surroundings, such as temperature, pressure, or humidity of the surrounding air. In addition, it is possible to predetermine permissible areas, such as on the ground floor of a building, that can be assigned to the object, such as inside a hospital. Objects can be measuring devices inside the hospital. In addition, in the area of the planning and monitoring of personnel deployment, a person can be assigned to an object node and the network can be used to request the location of the person and an access node can be used to actively communicate with the person at the object node. Determining the position of an object node can be carried out, for example, by evaluating proximity relationships of the nodes in the network or on the basis of known positions of anchor nodes as well as by evaluating reception signals at other nodes. This prior art reference does not relate to monitoring persons in tunnel systems. In particular, such monitoring involves conditions that make it difficult to reliably determine the position of persons and the areas in which they are located.
A position-determining device for persons taught by German Patent Reference DE 10 2006 034 857 A1 involves locating them in automated factories. In this case, the persons wear RFID tags that are read with the aid of reader devices provided in field devices. For this purpose, it is difficult to transmit variable data that arise with changing environmental conditions of persons or when people change positions.
European Patent Reference EP 1 047 244 A1 discloses locating a mobile node at a physical location in a network that can be a variety of sizes, such as occupying an office or extending across several countries. In particular, it is also possible to identify the mobile node in a foreign network. The mobile nodes can be connected to the network in various ways, such as by a local network, an infrared connection, or the like. This prior art reference involves selecting transmission paths for the data packets or IP packets, but not locating persons. In particular, specific problems arise when attempting to locate persons in a tunnel system.
PCT International Publication WO 2005/076553 A1 demonstrates the determination of the physical location in a network of nodes in which the distance to various nodes is used for locating purposes. This prior art reference also does not address solving problems that arise when attempting to locate persons in a tunnel system.
European Patent Reference EP 0 826 278 B1 demonstrates a method for routing data packets within a wireless packet-hopping network as well as a wireless network and nodes for using the method. It involves controlling the message paths for packet transmission, but not attempting to locate persons in a tunnel system.
Other devices for position-determining or locating are disclosed in PCT International Publication WO 01/06401 A1, U.S. Patent Reference US 2002/0104013 A1, German Patent Reference DE 103 23 209 A1, German Patent Reference DE 10 2006 034 857 A1, German Patent Reference DE 10 2005 055 102 A1, U.S. Patent Reference US 2004/0217864 A1, and U.S. Patent Reference US 2006/0219783 A1, most of which involve position-determination in buildings, frequently on the basis of RFID technology.